public HashSet <T> BreadthFirstSearch <T>(Graph <T> graph, T initialVertex)
{
var visited = new HashSet <T>();
if (!graph.AdjacencyList.ContainsKey(initialVertex))
{
return(visited);
}
var queue = new SortLib.Collections.Queue <T>(graph.AdjacencyList.Count);
queue.Enqueue(initialVertex);
while (queue.Count > 0)
{
var vertex = queue.Dequeue();
if (visited.Contains(vertex))
{
continue;
}
visited.Add(vertex);
foreach (var neighbor in graph.AdjacencyList[vertex])
{
if (!visited.Contains(neighbor))
{
queue.Enqueue(neighbor);
}
}
}
return(visited);
}
public Func <T, IEnumerable <T> > ShortestPath <T>(Graph <T> graph, T initialVertex)
{
var previous = new Dictionary <T, T>();
var queue = new SortLib.Collections.Queue <T>(graph.AdjacencyList.Count);
queue.Enqueue(initialVertex);
while (queue.Count > 0)
{
var vertex = queue.Dequeue();
foreach (var neighbor in graph.AdjacencyList[vertex])
{
if (previous.ContainsKey(neighbor))
{
continue;
}
previous[neighbor] = vertex;
queue.Enqueue(neighbor);
}
}
Func <T, IEnumerable <T> > shortestPath = v => {
var path = new List <T> {
};
var current = v;
while (!current.Equals(initialVertex))
{
path.Add(current);
current = previous[current];
}
path.Add(initialVertex);
path.Reverse();
return(path);
};
return(shortestPath);
}
